Microfossils of presumably bacterial origin were found in 2.7–2.8 Ga banded ferruginous quartzites in Karelia and the Kola Peninsula. The determination of organic carbon content and balance calculations showed that these ferruginous quartzites accumulated in an organic-rich environment. A comparative analysis of the morphology of modern and Neoarchaean microorganisms suggests the bacterial origin of some of the magnetite in the studied quartzites.
The larva of Cretoctesis conchimillanae gen. et sp. nov. from Burmese amber of Cenomanian (Middle Cretaceous) age is described. The new taxon belongs to the family Buprestidae, subfamily Polycestinae, tribe Polyctesini. It is the first formally described fossil larva of the family and the third species of the subfamily for the Cretaceous. Cretoctesis places the origin of the tribe Polyctesini in the Middle Cretaceous, them being the first taxon in the fossil record for the tribe.
Biomorphic microstructures of ferromanganese oxide ores are studied, focusing on the issues of types of microstructures, activities of bacterial communities that influence the formation of the structure of oxide ores, and determination of the basis of ferromanganese ore genesis. Ferromanganese oxide ores are a model object of bacterial paleontology for the quality and detail of their study.
Although coryphoid fossil palms are well-known from the Upper Cretaceous sediments of India, there is no fossil evidence of coryphoid palms from Siwalik sediments to date. Here, we report for the first time coryphoid palm fronds from the lower Siwalik strata (Chunabati Formation; middle Miocene) of Darjeeling foothills of eastern Himalaya. The leaf architecture, as well as the epidermal anatomy of the Siwalik specimens, suggests their resemblance with those of extant members of the palm sub-family Coryphoideae. The Siwalik specimens are characterized morphologically by palmate fan-shaped leaf with a well-preserved costa (costapalmate), prominent leaf segments emerging at an acute angle from the costa, numerous parallel secondary lateral veins on either side of the mid-vein, and anatomically by hypostomatic leaf blade, rectangular to polygonal epidermal cells, cyclocytic type of stomata and the presence of characteristic trichome bases. Based on a thorough comparison with earlier reported coryphoid palm leaves bearing epidermal anatomy, we placed our specimens under a new fossil species Sabalites siwalicus sp. nov. that is also supported by cluster analysis. The present fossils indicate that coryphoid palms were present in eastern Himalaya by the Siwalik time and they experienced a warm and humid tropical environment during the time of deposition.
For the first time, rostroconchs of the family Bransoniidae are described from the Lower Permian deposits of the Cis-Urals. The described assemblage includes three new species of three genera, of which two genera are new: Hoarepora uralica sp. nov., Ashaconcha rara gen. et sp. nov., and Agidelia magnifica gen. et sp. nov. The paper clarifies the systematic position of the family Bransoniidae, its diagnosis and composition, as well as the diagnosis and species composition of the genus Hoarepora Mapes in Mazaev, 2022. The species described here are the most ancient representatives of the family Bransoniidae, which were discovered on the territory of the East European Craton and the Urals. In general, taking into account the previously described representatives of Arceodomus, the Early Permian assemblage of rostroconch mollusks of the Southern Cis-Urals suggests a permanent paleogeographic connections of the Ural Strait in the Asselian and Sakmarian centuries with the basins of North America and the Tethyan Realm.
A nearly complete skeleton of a Mesozoic pterosaur, which probably belongs to Jeholopterus (Anurognathidae), was discovered in the third member of the Sinuiju Formation, Paektho-dong, Sinuiju City, North Phyongan Province, Democratic People’s Republic of Korea (DPRK). This find documents the first pterosaur fossil from the Mesozoic of DPRK.
Frozen mummies and their parts of the fossil Don hare are studied for the first time. They were found in permafrost deposits of the Upper Pleistocene in different regions of Yakutia: Verkhoyansky, Abyysky, and Nizhnekolymsky districts. Radiocarbon dating has shown that the studied hares lived in the second half of the Late Neopleistocene, 50.1–23.6 thousand years ago (the time of Karginian interstadial–Sartanian glaciation). A number of morphological adaptations of this extinct species to living conditions in the Arctic steppes of the Pleistocene of Yakutia have been identified: greater length and, apparently, body weight, short ears and feet, a strong locomotor apparatus of the hind limbs, hard hair brushes on the feet, and excellent heat-protective properties of the hair, including the specific microstructure of hairs. Comparison of the hairs of an adult individual and a month-old individual of Don hare has shown a polymorphism of the fur. The hairs are characterized by the presence of grooves, a columnar medulla, and a chevron cuticle, which allow an unmistakable identification of the taxon. In both individuals, specific hairs on the soles of the pads form a protective “cushion” that facilitates movement along snow, ice, and swamps. Based on palynological studies, understanding of the paleoecology of this species is expanded. Lepus tanaiticus lived in open landscapes: cold steppes dominated by xerophytic communities and grass–forb and sedge–forb meadows; unlike the modern mountain hare L. timidus, which generally feeds on shoots and bark of trees and shrubs in winter, the winter diet of Don hare included mainly herbaceous plants.
A specimen of Macaca was discovered in the Sungho cave no. 3, Sungho County, North Hwanghae Province, the Democratic People’s Republic of Korea. The only available skull remains are represented by a mandible, which displays a combination of mandibular and dental features indicating that the specimen may belong to the species Macaca mulatta. This discovery extends the geographical range of the genus Macaca.
Harsh environmental conditions of the study area result in low rates of ecosystem renewal. Results of geoecological studies at the sites of searching for and extraction of fossil remains of mammoth fauna in the middle reaches of the Indigirka River are presented. During the extraction of mammoth fauna remains using hydraulic washing-out, landscape components are disrupted, followed by leaching of the bedrock into creeks and rivers, thus leading to deterioration of abiotic components of the aquatic environment. Analysis of the geoecological state of the abiotic components of the ecosystem at the study site was used to assess the effects of the extraction of mammoth tusks by hydraulic mining. The study objects are cryogenic soils, bottom sediments and surface waters of the Semyuelyakh, Tirekhtyakh, and Indigirka rivers on the middle course segment. Soil and sediment samples were used to determine pH, mobile phosphorus, and Corg. Total content of Cu, Sn, Zn, Pb, Ge, B, Cr, Ni, V, Sc, Co, Ba, Sr, Nb, Zr, Y, Yb was analyzed using the spectral semi-quantitative method. The cationic-anionic composition, mineralization, suspended solids, pH and concentrations of Mn, Pb, Ni, Cu, Cd, Zn, Co, Fe were determined in surface water samples by atomic absorption spectrometry with electrothermal atomization. The concentration coefficients and anthropogenic load index were calculated. Studies conducted in 2022 established that there was a local impact on surface water. At the site of hydraulic pumping of water used to wash away the soil, an increase in mineralization, suspended solids, color index, and changes in the trace element composition were recorded, showing that manganese, nickel, iron, copper and zinc contribute the most to water pollution levels.
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